Various methods are utilized to secure and bond a trim layer to a foam pad. One such method developed by the assignee of the subject invention is disclosed in U.S. Pat. No. 4,692,199 issued Sep. 8, 1987 in the name of Kozlowski et al. The patent discloses a method of securing a fabric to foam pad which includes placing the fabric over a porous contoured mold, placing an air impervious adhesive film over the fabric layer, applying a vacuum to the mold to draw the adhesive film against the fabric layer to conform the fabric layer to the contours of the mold surface and eliminate any wrinkles, placing a similarly contoured foam pad in mating engagement with the adhesive film as it is held by the vacuum, compressing the foam pad against the mold by an upper perforated platen, and applying steam through the mold to heat and diffuse the adhesive film into the fabric layer and cellular foam pad to adhesively secure the two together. This process is very suitable for most materials. However, heating of the mold and platens may damage some types of upholstery layers, i.e., leather, making same undesirable.
U.S. Pat. No. 4,925,513 issued May 15, 1990 in the name of Witzke et al. discloses a method for manufacturing contoured seats which includes applying a heat activated adhesive layer to the upholstery, spraying an adhesive upon the foam cushion, and compressing the foam cushion against the upholstery and against the heat activated adhesive layer. The final step consists of applying heat to the heat activated adhesive layer to melt the adhesive and bond the upholstery and foam cushion together.
In any of these methods, it is necessary to decrease the processing time for bonding the trim layer to the foam pad, and eliminate the use of heat when using leather upholstery.